Telephone-receiver.



A. G. KAUFMAN &z L. J. LIPPMANN.

TELEPHONE BEGEIVER. .APPLIUATION PILBD PEB.7,1907.

900,38 7.' Patented Oct. 6, 1908.

2 BHEBTS-BEEET l.

A. G. KAUFMAN & L. J. LIPPMANN.

TELEPHONE REGBIVER.

APPLIOATION FILED 2131111901 900,:387. Patented Oct. 6, 1908.

2 BHEETS-SHEET 2.

U ITE sTA Esr ENT OFFICE;

ADOLPH'G. KAUFMAN' AND LEOPQLD J'. LlPPMANN,

' COMPANY, OF NEW YORK, NJY., A CO-RPOBATION OF' s 'ro MERICAN CALLAPHONE i (mesem OF NEW YORK, N. `Y., AssIGNoRs TELEP'EON'E-BEOEMB.

To all whom it muy --Bet knownthat we, noma G KAUF- nnx and J. Li mANN, both citizensof the -United State and reside'ntsof 5' the borou hofManhatta city, county,and| i State of ew York, hv invented certain new and useful Im 'rovem i Recevers, 'of whicii *the following is a speci- ,fictiotfl ourinvc'tiantelites to receivers for elec,- 'tric telephones and hasfor it's object to con-` struct a, sensitive receiver whi ch will pro- .du'ce sounds of great loudness'and clearness, enabling the transmitted s eech to be heard ata considerable distance" rom the receiver, and also to insulate the-receiver against the transn'sion of extraneous noises. The invention will be full described hereinafter, and the features' o novelty pointed out in the appended claims. v 'Reference s to be had to in drawings, in which igire 1 s a sectional ele'vation of a tele- ?hene receiver embodying our invention; A i 2 is a detail View of thereceiver agnet an its connections, drawn upon an ex i i'arged scale; Fi 3 is a "vertical section' on line 3-.-3 of ig. 1; Fig. 4 is a rear View showing' another form of our inven'tion; 5 shows still another form of our inyeton, illustratiig only the magnefs with their polepieces, s' ools and the socket which receves -tle diap ragm hol der; and Figs` ..6, 7, and 8 are detal views-showing const'ru'ctions of the magnet pole'piees. o In the Construction represented invFigs. 1, 2 and 3, Ais'asuitable casing which we prefer to secure elastically to the wall late or other sup ort B, asby meansof springs C. In order t a't dust may be excluded irrespective of any m'otion or .vibration'o the casing A, an expasble shield or curtain, such as -the bellows D, may bridge the' opening be th'feen thecasin and its SHE ort B.

`.Th'e front wal A' prefera i; forms adoor 4 which may be -o ened to give access to the ma net E and ot er parts within the casingi Ths magnet we generallyarrange so that it will becomparatively free, that is racticallybut of contact with the walls of t e casin .For this purpose, a distance piece F (o Wood or other suitable materal) may be located between theft-ont wall A' and the middle portion of the magnet E, while a cross bar G is located against the rear surthe accornpany'- s mcation 'of zemr- Patent. engon od ramm 7, 1007. ;na ne. man.

fron) its support or' fast'enn'g,

nts in Telephone-" distance" and are partIy surroind'ed by the socket 4 A socket which is therefore carried by the 'mg- 4 justed to different fpositions.

' const-ruction shown,

-cidental displacenent by meanso Patented Oct. e, mos;

faceof thenn'ag'net, this crossbar in con-. unction with screws'H, servin to'iasten .the maget'to the front wall or i oor A'.` The' magnet thus projects i-n opposite directions the ends or.` &mctmg portions being practically free he magnet is preferably 'lamellated, as

carrying pole pieces E', by means of ieces E which may be non-m netic, an screws-ES' which in the prese t sa case are of'ma netic material. In' any event, there should-%e a connection' of magnetic y shown,

'material from the magnet to thepole pieoes E but each pole 'piece'slonld be magnetic-- ally separated from other., The; pole pieces, which forsecuringthe best results should 'have par-alle] slits as shown, Carry i thecustomiry spools I' of insulated wre with suitable connections to binfling as shown' best in Fi 3.

.pole pieces and spoo' 's are -the casing A (thedistance posts J, Prefera ly the 4 located outside ieces E pr'oject ing through an opening in t e front wall A' Secured in p ce by -the screws E'. The net is-'scre'w threatledexterna'llyto receive .the box' L, providedwitha clamping late L' to hold the diaphragm M. To the c ampir plate L' is'secured centrally atube L' onw i s mounted one end of an amplif-ying hon. N, capable of turning on said tube and held in position by means of a clamping ring N'; The amplifying horn may therefore head'- We preier to and gradually fieri andwe have discove that .this Construction' roduces better results than a strai ht ampli 'ng horn. The olte' end of the orn is eccentric'and one end isarallel to the other, both being perpendicuar to the lane of the diaphra It will be observ that.the` diaphragn box .L with the diaphragn M and the horn N are carried directly by the magnet and' will .therefore always' remain in 'the same position' relatively to the magnet, (even should-the-latter vibrate) 'unless the adjustment is 'chan by screwing the box L on its socket K.

The distance between the, diaphragm M and -the pole pieces ofthe magnet may be employ the curve K, and when the proper adjustment has been obtained, the part:: are Secured' againstano a' nu 4 4 su-bjectecl.

p'oles of both magnets.

which is prefcrably locatedontside the casing A so that the appa'atus need not be opened or taken apa't in order to etfect the adjustment.

The peculiar way of supporting the inagnet 'so that 'it is tree in almost its entire length rendere the deviee 'very sensitive and the magnet almost entirely independent ot any vibrations of the casing A. 01' .its cover AQ Thoelaotic support or suspension of the casing eai'egna'cls itin a large neasu'e against' the t'ansn'ission of Vhratio's ti which the support 01' wall plote B may be In the Construction illustrated. by Figs. 1, 2 and 3, the magnet- E is'a simplehorseshoe magnet of the lamellated type. In 1 1%. 4 ike i two such n'agnets E* are employed with poles adjaeent to each (wher, and each pole piece is nagnetically connected withlike The Construction of the casing and themanncr of securing the magnet, diaphragm, and amplifying horn thereto, may be the same as' described With reference to Figs. 1, 2, and 3.

In Fig. 5 the two lamellated magnets E form :1 rectangular figure with centrally disposed and inwardly directed ends E Tom each of which a pole. piece E projects -at a right angle. The sections of" these pole pieces are sepa'a'ted by elite as hown and may be made to folim a en've with their oute' edgea so thatthe magnetic action on the daphragm W ll be more effective.

In.F1g. '6, each pole pece's shown -as of rectangular or angle-iiton shape, with slits i being shaped to eonform with the 'E in one of its members.

These slit pole peccs may be made to toi-m a cnrve W'llll' the outet and inner edges, as shown in'Fig, 8. In Fg. '7 individual. pole pieces E areemployed and Secured tog ther by a screw e. The other parte of this structure may be the same as' before described, thes ools I". po epieccs E inFigs. 5 and 8.

Most of the features disclosed herein are contaned in an earlier' application filed by us in the UnitetTStates Patent Office, No- Vember 13, 1.906', Serial No. :343,19&

XVe claim as our invention: 1. A telephone .receiver, comp'ising a cas'- ing; a magnet support thercin a 'magnet carried' by 'said support and projecting in opposite directions therefmm, pole pieces at the ends of the manet, coils on said pole peces, at dla hragm ox car'cd bythe mag-. net 'ndeper enti" e* the casng, and a dia phragm located in ;aid box adpcent, to the i pole'pieces.

2. i\ telephone rcceivor comprising a' casn'g, a magnet supported theren, magnet ':oi1s, a diapl-agn box carried by the magnet directly and independcntly of the casing and a diaphragm in said box.

3. i\ telephone 'eceiver eon'iprsing a 'casing, a n'agnet supported. thei-vin magnet coils, a diaphragn box cariied'liy 'the nagnet directly and independently of the casig V and ad ustahlc toward and from the magnet,

and a diaphragm in. said box.

4. A telephone reeeve' con'prsng'a magnet the pole pieees of which having opposite' pola-itv are located alon side of one another, each o said pole-pieces aving a lateral odset for connecting 'it to the n'agnet and being provided with plurality of slits and a cn'ved onter edge.

5. A telephone 'ccei'erconp'ising apasing,' a magnet supported the'ein, magnet 'cols, a serewthreaded socket Secured to the magnet directly and supported independently'of the casing, a diaphragm box having a-scrcw connection with said socketgand a diaph-ag''-n said box.

6. A telephone 'eceiver comprising a casing, a magnet Supported therein, a sockct secured to the magnet directly' and supported independe'tly of the casing, pole pieces and magnet coils within said socket, a diaplragm lox car 'ied by said `eocket adjustably, and a. diaphragn in said box.

7. A telephone rcceivcr conprising a (rasing a magnet supported therein' at a dis 'tance from pole pieces so ae to give the lattor considerahle freedom, a diaphragm 'box car'iedilii'ectly by the polo piece poi'- tions of th magnet ndcpcnde' tly of the esngnn-df moyble-relatively to the casing in nnisoL-syithsaid magnet'portions, and a 'diapl'ragm in ;said box'.

8. A telephone receiver (-omp'ising a casing a magnet supported the'ein at a distance from its: ;ole pieces so as to give the letter eonsidefiilfreedom a diaphragm box car- 'riedfadjnStahly bythe pole piece' po'tions of the magnet 'dependently of the casi ng and V at'fVely to the casing in' nnison with Saidnagn porfions, and `a diaphragm in saidboxg a 'In testi nony' whereof, we have signed' this specifiation in thepresence of two subscrily ing'nfitnesse V I ADOLPH G. KAUFMAN. IQLEOI'OLD J. LIPPMANN.

W i tnesses i OTTO v. Somnx'c, ,Tony Lot n. 

